update_ad_group

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations declare readOnlyHint=false, consistent with a mutation tool. The description adds that it is a partial update ('Only the fields you pass change'), which is useful. However, it lacks details on side effects, permissions, idempotency, or whether unchanged fields remain untouched (implied but not explicit). The transparency is adequate but not exceptional.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is a single, information-dense sentence. It front-loads the key action and behavior, with no extraneous words. Every part adds value.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given 100% schema coverage and existence of an output schema, the description is reasonably complete for a straightforward partial update tool. It covers the primary behavior, though it could briefly mention required parameters (campaign_id, ad_group_id) or preconditions (ad group must exist). Still, it provides sufficient context for an agent.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, with each parameter described in the schema. The description reinforces partial update semantics but does not add meaning beyond what's already in the schema. The baseline 3 applies as the description does not compensate for missing schema information.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the action ('Update'), the resource ('existing ad group'), and the key behavior ('in place', 'Only the fields you pass change'). This distinguishes it from siblings like create_ad_group (creation) and delete_ad_group (deletion). The verb+resource+scope is specific and unambiguous.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description does not explicitly state when to use this tool vs alternatives (e.g., creating, deleting, or other update tools). However, the name and partial update hint imply its purpose. No concrete usage boundaries or when-not-to-use guidance is provided.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.